[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 6861d93 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   6861d93..db6f7e0  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to db6f7e0e9ec20049bfbb7c965baa90e1b9e56d3f.
CMake Error at CMakeLists.txt:3 (cmake_minimum_required):
  CMake 3.13.4 or higher is required.  You are running version 3.7.1


-- Configuring incomplete, errors occurred!